Floor-surfacing machine



M. G. POND FLOOR SURFACING MACHINE Filed Oct. 6. 1924 2 Sheets-Sheet 2 INVENTOR. Mark/#6 o/va/ b Y 4 Patented duly 13; 1926.

UNITED @TATEfi j 1,591.59 PATENT Q FECEa MERRITT G. PQND, F Illl:INNEAPOLIS MINNESOTA, ASSlIGNOR, BY MEfiNE ASSIGN- MENTS, TO ADVANCE MACHINE CO., INC., OF MINNEAPOLIS, MINNESOTA, A COR- PORA TION OF MINNESOTA.

FLOOR-SURFACING MACHINE.

Application filed October fig, 1924. Serial No. 741,991.

' v(My invention relates to floor surfacing machines and has for its object to provide a machine adapted to adjust itself to the contour of the floor upon which it is being used, so as to give uniform pressure throughout the grinding surface of the device.

Another object resides in providing two inter-meshing plates having grinding elements thereon, which plates are driven by intermeshing gears, one of which is driven from a pinion secured to the shaft. of a motor.

A still further object is to provide universal joints between the grinding plates and their driving elements, so that the same bear down uniformly upon the surface to be ground.

Another feature of the invention resides in providing a single supporting wheel in conjunction with the frame of the device and said grinding disks which carries a portion of the weight of the device and also permits of readily directing and steering the machine.

Another object of the invention consists of providing auxiliary supporting wheels which when the device is inoperative position are not in engagement with the floor -but which upon raising the grinding disks away from the floor, come into engagement wherewith toassist in supporting the structure in conjunction with said single wheel, or independently thereof if desired.

Other objects of the invention reside in the detailed construction thereof as disclosed in the following drawing, specification and claims.

in the drawings illustrating my invention in one form? Fig. 1 is a side elevational view of my invention in operative position with a portion removed.

Fig. 2 is a view similar to Fig. 1 showing the. same device withthe grinding members in disengagement with the floor.

Fig. 3 is a bottom view of the device shown in Fig. 1.

Fig. 4is a view similar to Fig. 1, illustrating a modification of the invention.

Fig. 5 is a fragmentary view of a modification of the invention.

In floor surfacing machines where a number of rotary'grinding members are used, it is highly essential that uniform pressure be had upon all of the embers, in order that a uniform cut be taken for the. entire width of the cutting surface. At the same time it is desirable to provide auxiliary supporting means which permit of lateral adjustment so that the grinding members may properly adjust themselves to cut uniformly across the-width of the grinding surface. I accomplish these results by employing a single supporting wheel having preferably a crowned or a narrow face and also in using in conjunction therewith. auxiliary supporting wheels which are adapted to come into engagement with the floor when the machine is swung on the single wheel to bring the grinding surfaces out of engagement with the ground as becomes essential in the transporting of the machine from one locality to another.

In the drawings in Figs. 1, 2 and 3, I have shown a supporting frame substantially planiform in formation which is provided with an upturned edge 1l having.

an outwardly extending flange 12-. Upon this frame l0 is positioned a cover -13 having a downwardly extending edge -14- formed with a flange -l5 which is adapted to rest upon the flange 12, and is bolted thereto. means of this construction an enclosure or casing is formed which is indicated in its entirety at -l6 and which contains the gearing for driving the rinding plates as will be presently describe On the under side of the frame member --1()- is formed two spaced bearings -17-- in which are journalled' shafts -l8. These shafts extend up into the casing 16 and have attached to them a pair of intermeshing gears --19' and 20--. On the top of cover --13 is positioned an electric motor 21- which has a inion 22- secured to the end of its drivmg shaft. This motor is of the vertical type and the pinion 22- extends down -27 and the plates 23 and 24-.

In a similar manner a corresponding number of studs 29 are employed which are attached to the plates 23' and 2 1- and to the disks 30 in staggered relation to the studs --28. In this manner the thrust or force imparted to the plates 23- and 24: is transmitted through the lugs -26 and sockets -25-in said plates while a universal rotary motion is given said plates through disks 30 and the structure attached thereto which serve as universal joints in driving said plates;

For grinding purposes the plates 23 and 24 are each formed with three outwardly extending arms 31 -32 and 33- which intermesh each other as best shown in Fig. 8. These arms carry carborundum stones 34 which are held in place between ridges -35 formed on said plates, by means of wedges 36 securely driven between said ridges and stones. As

the motor 21 rotates, the plates -23 and 24 rotate in opposite directions, the stones 34 grinding the surfaces with which they come in contact. It will be noted that the stones on one plate travel in a path overlapping those in the other plate so that a cut is secured which extends throughout the entire width of the combined grindlng plates.

As can be seen in Fig. 1, the device is supported on a single wheel 37- as'well as the grinding plates 23- and 24 when in its operative position. A recess--88- is formed in the frame 10- between which this wheel is positioned, bearings 39 and -40- secured to the under side ofsaid frame, serving as journals for the axle of said wheel. To permit the plates 23- and 24- to follow the contour of the floor, the wheel 37 is formed with a crowned face -41 or the same may be made quite narrow.

In moving the device a handle 42 is provided which is attached to the frame lO-- and braced by braces 43 to the cover -13-. By this means the entire machine may be guided about the floor while the grinding or surfacing'is taking place.

When it is desired'to disengage or raise the grinding plates -23 and 24- from the floor, the entire machine is swung back on the wheel 87-. as shown'in Fig. 2. To prevent the machine from toppling over,

two auxiliary wheels 44 and 45 are employed which have their axes in about the same plane above the floor as wheel -37 but which wheels are of lesser diameter so that the same do not normally engage the floor while the machine is in 0 eration. These two wheels are journalle in bearings 46- and 47 which are rearwardly positioned relative-to wheel -37 and which are attached to the underside of frame 10 the same as bearings -39- and 40. As the handle 4=2 is lowered, these wheels enga e the floor which steadies the machine an permits the same to be wheeled about from place to place. When it is desired to replace the grinding stones -34 the handle -42is lowered until it touches the floor which gives free access to the underside of the machine.

In Fig. 4, I have shown a modification of the invention in which the wheels are all mounted on a single shaft 48. In this case the wheels 44 and 45- are also smaller than the wheels 37 so that in operation these wheels do not engage the floor. As soon as the machine is tipped up, one or the other of these wheels comes into engagement with the floor to assist in supporting the machine, the machine tilting a little to one side or the other.

If desired the wheels 44 l5 and 37 may be mounted on a single axle 51 and the wheels 44 and ,45 eccentrically positioned thereon relative to wheel 37 asshown in Fig. 5. By manipulating a lever 49 pivoted to an arm 50 secured to shaft or axle 51- the same can be rotated to bring the wheels -44 and 45 in engagement with the ground.

My invention is advantageous in that it provides a simple and eificient construction. By employing a single sup orting wheel the machine automatically ad justs itself to the contour of the floor thereby smoothly and uniformly grinding the same. There are a minimum number of parts to get out of order and the machine is so desi ned that the weight of the motor serves to ar down upon the grinding plates when in operation and to hold the structure in raised osition when the handle has been tilted Having described my invention in a particular form and having disclosed the same as applicable to a single use, I desire to have it understood that the same may be constructed in other ways and put to uses other than those recited within the scope of the following claims: I 1. A floor surfacing machine comprising a frame, a motor mounted thereon, a grinding device mounted on said frame and driven by said motor and a single sup rt' 'ingwheel of a width less than that o the grinding device for supporting said frame and motor in Conjunction with said grinding device and a pair of wheels mounted on said frame normally raised above the floor and being adapted to engage the floor upon raising said grinding device.

'2. A floor surfacing machine comprising a frame, a motor mounted thereon, a grinding device. mounted on said frame and driven by said motor and a single supporting wheel of 'a width less than thatof the grinding device. for supporting said frame portion pf said frame, a motor mounted on said casing, a pair of grinding plates jour-' nalled below said frame near the forward part thereof, transmission mechanism within said casing for driving said plates from said motor, said frame being formed with a rearwardly extending central recess starting at said casing, a supporting wheel having a crowned face journalled to said frame and positioned within said recess, a pair of auxiliary supporting wheels rearwardly positioned relative to said first supporting wheel and normally elevated above the floor and a handle extending rearwardly from the rear portion of said frame.

4. A floor surfacing machine comprising a frame, a motor mounted thereon, a pair of grinding plates mounted on said frame and simultaneously driven by said motor and a single sup orting wheel positioned between said grinding plates and rearwardly there from'.' i

5. A floor surfacing machine, comprising aframe, a motor mounted thereon, a pair of grinding plates mounted on said frame and simultaneously driven by said motor, a single supporting wheel p sitioned between said grinding plates and rearwardly therefrom, bein of a width less than either of said grinding plates for supporting said grinding plates in operating position, and auxiliary wheels for supporting said machine with the grindingplates thereof in.

elevated position. v

- 6. A floor surfacing machine comprising a frame, a motor mountedthereon, a pair of grinding plates, means for driving said grinding plates from said motor and for flexibly supporting the same relative to one another, a single supporting wheel positioned between said grinding plates for permitting flexure of the plates relative to one another, and a pair of auxiliary wheels rearwardly positioned of said supporting wheel and above the plane of said plates, adapted to engage the floor when the machine is tilted back upon said supporting wheel to hold said grinding disks in elevated positron.

7. Afioor surfacing machine comprising a frame,a motor mounted at the forward portion of said frame, a pair" of grinding plates journalled below said frame near the forward part thereof, means for flexibly supporting and drying said plates from said motor, a' supportingwheel journalled to said frame and positioned between said plates rearwardly thereof, a pair of auxiliary supporting wheels rearwardly posi tioned relative to said first supporting wheel and normally elevated above the floor, and a handle extending rearwardly from therear portion of said frame.

8. A floor surfacing machine comprising a'frame, a motor mounted thereon, a grinding device mounted on said frame and driven by said motor, a single supporting wheel for supporting said frame/and motor in conjunction with said grinding'device, a pair of wheels mounted onv said frame normally raised above the floor, the center of gravity of said machine lying between said single wheel and'said grinding device causing said machine normally to rest upon said-- grinding device and single supporting wheel, and a handle extending rearwardly of the machine for tilting said machine back upon said pair of wheels so as to raise said grinding device above the floor.

9. A floor surfacing machine comprising a frame, a motor mountedon said frame, a grindin device mounted on said frame and driven by said motor, a single supporting wheel positioned rearwardly therefrom for supporting said grinding device in operative position, and auxiliary supporting means normally raised'above the ground adapted to come into supporting position upon tilting said machine so as to raise said grinding device above the ground, the center of gravity of said machine falling between said grinding device and said single supporting Wheel.

10. A floor surfacing machine comprising a frame, a motor mounted thereon, a pair of grinding plates mounted on said frame and simultaneously driven by said motor, and a single supporting wheel positioned between said grindmg plates and rearwardly therefrom, the center of gravity of said machine falling between said grmding plates I and said single supporting wheel.

In testimony whereof I 'a-flix my s1 nature.

MERRITT o. r ND.

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